3.2. Third party's procedural rights

According to Art. 115, second sentence, EPC a third party does not become a party to the proceedings. In principle, therefore, third parties have none of the procedural rights associated with such status, in particular the right to appeal and the right to be heard (T 1756/11; G 2/19, OJ 2020, A87). In T 831/17 of 21 October 2019 date: 2019-10-21, the board observed that the EPC legislator had decided to confer a right of appeal only on parties to proceedings and not on authors of third-party observations. It was held in G 2/19 that a third party does not become a party to proceedings by virtue of its comments having been considered in those proceedings. A third party's lack of status as a party to the proceedings also goes hand in hand with a lack of any adverse effect, for legal purposes, ensuing from the decision taken in those proceedings. That is consistent with the object and purpose of Art. 115, first sentence, EPC.

In T 951/91 (OJ 1995,202) the board found that by interpreting Art. 115 EPC 1973 in the light of their object and purpose, it was clear that they were intended exclusively to cut down, and not to extend, the rights of third parties, still less to extend their rights beyond the rights of parties to the EPO (see also T 1756/11, T 1528/13 and T 2255/15).

According to T 390/07 the admissibility of third-party observations is entirely a matter for the board as a third party within the meaning of Art. 115 EPC is not a party to the proceedings and has no more than an opportunity to "present observations". While it is well-established by case-law that third-party observations can be considered, both at first instance and on appeal, there is no obligation on the board beyond such consideration and no right of a third party to be heard on the admissibility of its observations or any evidence in support of them. The actual parties to proceedings naturally have the right to be heard in relation to such observations, but their admissibility is entirely a matter for the board. Parties to the proceedings can comment at any stage on new facts and evidence emerging from third-party observations filed after expiry of the opposition period, if they think that these could influence the decision. The opposition division or the board of appeal, exercising its discretion, is then obliged to rule on whether or not to admit the late-filed comments into the proceedings (T 1756/11).

In T 283/02, the opposition division had duly forwarded the observations by third parties to the patentee, who had made no comment. The failure of the opposition division to mention these observations in its decision did not constitute a procedural violation, even though a mention would have been desirable.

In G 2/19, the Enlarged Board held that a third party within the meaning of Art. 115 EPC who has filed an appeal against a decision to grant a European patent has no right to have its request for an order that examination proceedings in respect of the European patent be reopened for the purpose of removing allegedly unclear claims (Art. 84 EPC) heard at oral proceedings before a board of appeal.